Vacuum cleaner muffler



Aug. 2, 1938. A. E. NoRRls VACUUM CLEANER MUFFLER Filed Feb. 27, 1957 www' WITNESS INVENTOR /71 fwf ,5. /l/o ,qw/s BY ATTORNEYS Patented Aug. 2, 1938 VACUUM CLEANER MUFFLER Alfred E. Norris, Westeld, N. J., assignor` to The Regina Corporation, Rahway, N. J., a corporation of New Jersey Application February 27, 1937, Serial No. 128,108

13 Claims.

The invention relates to a vacuum cleaner of the usual household type consisting of an ambulant frame, motor, suction fan, suction nozzle, dust bag, and a handle attached to the frame for guiding the cleaner over the surface to be' cleaned.

More particularly, the invention relates to a novel construction of muiiler incorporated in the bag of the standard type of such apparatus. Such muiiier structure is designed for effectively reducing to an appreciable extent the noise emityted by the vacuum cleaner in operation and is characterized by certain features of construction such as the manner of supporting the same within the dust bag of the vacuum cleaner, conducive to producing the most eflicient and effective functioning of the mufer, while at the same time contributing in large measure to the sturdiness of the structure and its ability to withstand shocks to which it may be subjected in the or-'- dinary course of use of the cleaning device. My novel form of mufer structure and its support in the dust bag are characterized also by certain .advantages,'for instance in facilitating the operation of cleaning the dust bag.

The general form and structure of my novel muiiler device is that described and shown in the application of Ernest J. Abbott, Serial No. 89,568, filed July 8, 1936, in which such general form of muffler structure is included in a blower unit, ior

instance, a vacuum cleaner, for the purpose of effecting a marked reduction in the usual noises emitted by a blower unit during its operation.

The present invention embodies certain improvements in the construction and manner of supporting a muiiier ofV such general type and is designed to overcome certain disadvantages attendant in the use of a muffler which does not vembody the particular features of novelty hereinafter to be described.

One of the objects of the invention is to provide a muier structure of unitary construction, including a means, integralwith the body of the muler, for connecting such body with the collar constituting the ingress means for the air blown through the dust bag.

One form of connection as between the body of the muffler structure and such ingress collar, as disclosed and described in the Abbott application hereinabove referred to, is a rubber tube disposed between the outer periphery of the dust bag -collar and the turnedin portion of the mouth of the dust bag. The muiiler in such construction is constituted of a perforated cylindrical screen surrounded by'a .packing of wood nbre,A

the fibre and the screen being contained within an outer shell.

I have found that when employing a rubber tube as such connecting means, if such tube is sufciently flexible to readily conform with all positions that thebag may assume while the cleaner is in use, the rubberfconnecting tube will tend to collapse whenand as the mullier moves out of alignment with the central line of discharge, thereby constricting the passage through the tube and interfering with the free passage of air. On the other hand, if the tubing is made sumciently rigid to prevent this tendency to col-v lapse, the muflier because of its more rigid position in the bag, will interfere with the normalv operation of the bag.

In accordance with my invention, therefore, I employ anovel construction of flexible tubing which is in the form of an accordion or bellows, and, in the preferred embodiment of my invention, such accordion-like flexible tubing is integral with the casing of the muiiier within which the perforated cylindrical screen and wood fibre packing are contained. In this manner, I secure a flexible connection between the muflier body and the dust bag collar, which is provided with means, pleats in the now-preferred embodiment of my invention, to prevent, when the connection or tubing is bent, any alteration of the effective cross-sectional area of such tubing.

A specific embodiment of the novel structure of a dust bag muilier constructed in accordance with my invention is illustrated in the accompanying drawing, in winch Fig. l is a side view of a typical standard type of vacuum cleaner; Fig. 2 is a sectional detail view of a portion of the dust bag of such cleaner, to which the muiiier constructed in accordance with my invention has been applied; Fig. 3 is a section on the line 3--3 of Fig. 2 and Fig. 4 is an enlarged sectional detail of the manner of securement of the muffler structure to the dust'bag.

REISSU ED JUL 3 o 1940 Referring more particularly to the drawing, in

which similar reference characters identify similar parts in the several views, Il` is the ambulant frame of the vacuum cleaner comprising a case' or housing II for a horizontal motor, and a suction fan housing I2. The frame I0 and motor case II are mounted on pairs of wheels I3 sup- I6 to which is connected the usual dust bag I1 used with this type of vacuum cleaner. Pivotally mounted upon the shaft near the ends of which are secured the wheels I4, is the forked member I 6 to which is connected the tubular handle I9 having the handle grip 20 and within which is secured a portion of the electric cable 2 I.

Secured to the end of the discharge pipe I6 by a. bayonet joint is a dust bag collar 22. To such dust bag collar are secured, as shown clearly in Figs. 2 and 4, the dust bag I1 and the muffler housed therein by means of a collar attachment wire 23 and a rubber ring 24 stiffened by a wire core 25.

The end of the dust bag collar extends into the dust bag I1 and has secured to the outer periphery thereof a rubber tube 26 constituting a portion of the molded rubber housing of the mumer structure. Such rubber tube encompasses both the turned-in portion of the mouth of the dust bag and the dust bag collar, being secured in position by rivets 21--21.

'I'he portion of the muffler housing designated as the rubber tube 26, is formed with a plurality of pleated sections 28, which sections form an accordion-like tubing, the peripheral wall of such tube in longitudinal section being formed of a plurality of bends, as clearly shown in Fig. 2. In the particular embodiment illustrated in the drawing, the tube 26 as shown. is constituted of an accordion-like member having three pleats. but it is obvious that any number of such pleats may be employed, so long asA a bellows effect is secured for the purposes hereinafter to be more fully described.

Near the end of the accordion-like tube structure, removed from the dust bag collar, there is secured, so as to have the end thereof enter the rubber tube, a perforated cylindrical screen 29. The portion of the rubber tube 26 which extends over and upon the end ofthe perforated screen is crimped over such end by means of a wire 30.

Surrounding the perforated screen 291s a packing of wood nbre 3| contained within the outer shell 32, which is preferably of rubber and preferably integrally molded with the tube 26 so as to constitute a housing for the packing o f wood fibre and perforated screen. The outer shell 32 is formed with a mouth 33 overlying the end of the perforated screen remote from that which is secured to the tube 26. ,The end portion of the outer shell forming such mouth and which is in contact with the perforated screen, is crimped over the end of such perforated screen and is secured thereto by means of a wire 34.

Molded integrally with the rubber outer shell 32 and extending from the mouth portion thereof 33, are two tabs 35, 36, for a purpose hereinafter more specifically referred to. To one of such flaps 35, being that which is the upper one when the muffler structure is secured within the vacuum cleaner dust bag, is secured by rivet 31, a tape 38 which at its other end is secured to the inner face of the dust bag at a point which will permit the mullier structure to be supported within the dust bag in such position as to have the axis of the muffler, and more particularly the axis of the cylindrical perforated screen, substantially in alignment with the egress end of the discharge pipe I6, as is clearly shown in Fig. 1.

'Ihe muiller constructed in accordance with my invention, therefore, comprises a molded outer shell or housing, a portion of which is constituted of a rubber tube of accordion-like structure having a bellows configuration which extends from the dust bag collar, a length of perforated screenlng extending from the end of such rubber tube and housed within the outer shell of molded rubber, and a quantity of wood fibre packed between the shell and perforated screen. The wood fibre is packed in such manner as to have its fibre disposed radially of the perforated screen and outer shell.

The novel muffler structure just described, including an acoustic absorption material is effective in reducing the noise produced by the vacuum cleaner in operation and is effective so as to reduce such noise without interference with the filtering function of the bag and without any interference with the air flowing therethrough.

The novel construction of dust bag muffler in which the flexible connection of the muffler to the air inlet is constituted of an accordion-liketube, has a number of advantages which will now be more specifically set forth.

As hereinbefore stated, when an ordinary rubber tube is used as a flexible connection, such ordinary rubber tube will tend to collapse when and as the muffler moves out of alignment with the central line of discharge and constrict the passage through the tube. By forming such connecting tubing in the form of a bellows structure or, as hereinabove described, with a plurality of pleats so as to form such tube in the shape of an accordion, the muffler can be supported by such tube connection without the tube collapsing, no matter to what extent the tube may be bent. Thus, it will be seen that if the position o1' the muffler structure is to any extent changed from that in which itis in perfect alignment with the central line of the discharge pipe IIS, the effective cross-sectional area of the passage through the connecting tube will be maintained constant, as no collapsing of such connecting tube can take place, there being suflicient material provided by the pleats to take care of any extension at any point along the length of the tube.

The flexible connection as particularly described hereinabove, has the additional advantage that in the course of cleaning the dust bag, which operation includes the removal of the dust and dirt collected therein, the muffler structure itself acts in the nature of a bell clapper. In performing the cleaning operation, the dust bag containing the muffler structure is removed from the frame and may be held by the collar 22 and the dust bag shaken. The accordion-pleated flexible connection between the muffler structure and the dust bag collar will permit the muffler structure to act as a bell clapper, striking the sides of the dust bag while the bag is being shaken so as to loosen particles of dust and dirt which have adhered to the sides of the bag.

The dust bag structure and novel connection thereof which, in accordance with my preferred embodiment, are constituted of a single piece o molded rubber forming the connecting tube ai d the outer shell, has the additional advantage of being capable of withstanding the many knocks to which the vacuum cleaner is subjected both during use of the cleaner and during the operation of cleaning the dust bag. Furthermore, by making the outer shell of the muffler structure of rubber, molded in one piece with the flexible connection, any wearingof the bag by contact with the inner surface thereof by a metallic shell,

- is prevented.

The molding of the outer shell in one piece with the exible connecting tube also permits easy and rapid assembly of the muffler4 structure.

By providing the flaps 35 and 36 at the mouth of the rubber shell 32, there are provided means by which the mouth of the outer shell may be extended with facility for the introduction into the shell of the perforated cylindrical screen 2S through such mouth and the easy and rapid packing of the wood nbre into the space between the perforated cylinder and the outer shell. This is accomplished by graspingy the two flaps 35 and 3B and pulling them apart to an extent suillcient to enlarge the mouth of the'shell to permit the insertion of the perforated tube and then the packing of wood fibre. Wh'enthe ilaps are released, the mouth will be again contracted so as to overlie the peripheral surface of the perforated screen and the wire 34 may then be secured in place.

Mention has been made hereinbeforeof the ef- Y fect of the dust bag muiller structure, just described, in reducing the noise emitted by the vacuum cleaner during operation.. This is due in great measure to the use of a rubber shell which serves, together with the accordion-pleated flexible connection, as a noise-dampening element. 'I'he reduction in noise is marked' and readily noticeable in a comparison of the noise emitted muiiler structure constructed in accordance with my invention and a dust bag muiiler structure not embodying the features of ovelty herein disclosed.

While I have described a specic embodiment of my invention, it is obvious that various changes may be made therein, particularly in the arrangement and configuration of the several .elements described, without departing from my invention.

vI claim:

1. A muiiier structure, comprising an acoustic absorption material, for the dust bag o! a vacuum" cleaner including a flexible tube connection between the muiller elements and the dust bag collar, said flexible tube connection having means to prevent any alteration in the effective interior cross-sectional area of the tube when such tube is bent.'

2. A mumer structure for the dust bag of a vacuum cleaner comprising a cylindrical perforated screen, a body of fibrous material surrounding the screen, an outer shell containing said screen and said body of fibrous material and a flexible. connection between said outer shell and the collar of the dust bag, said outer shell .and said .flexible connection being formed of a single piece of molded rubber.,

3. A muilier structure for the dust bag of a vacuum cleaner comprising a cylindrical perforated screen, a body of fibrous material surrounding the screen, an outer shell containing said screen'and said body o! iibrous material and a flexible connection between said outer shell and the dust bag collar, whichY flexible connection comprises a rubber tube provided with means to4 maintain constant, when saidtube is bent, the eilfective interior cross-sectional area ofthe air passage -within said tube., said outer shell and said exible-oonection being formed of a single piece of molded rubber.

4. In a @vacuum cleaner, an ambulant trame,

a dust bag, said dust bag having a mufiler struc-, ture, comprising an acoustic absorption material, flexibly mounted therein by means of an accordion-like rubber tube.

5. A vacuum cleaner having an ambulant frame, electric motor, suction fan, suction nozzle and a dust bag, a muiller structure, comprising an acoustic absorption material, mounted in said dust bag, and a iiexiblevconnection, in the form of a bellows structure, between said muiiler and dust bag inlet.

6. A muilier structure as claimed in claim 2 in which the outer shell is provided with a constricted mouthhaving a pair of tabs by means of which said mouth may be enlarged.

7. A muiller structure as claimed in claim 2 in which the outer shell is provided with a constrictedmouth having a tab and a tape connection between said tab and a point on the interior surface of the dust bag for supporting the muffler structure in a position of alinement with the dust discharge pipe of the bag. l

8. A muiiler structure as claimed in claim 2 in which the outer shell is provided with a constricted mouth having a pair of tabs by means of bag. v

9." A muiiier structure f or the dust bag of a vacuum cleaner comprising a cylindrical per forated screen, a body of an acoustic absorption material surrounding the screenf-and anl outer shell of a single piece of molded rubber 'containing said screen and said body of acoustic absorptionl material.

10. A mumer structure as claimed in cl 9 in which the outer shell is provided with a ns'tric'ted mouth having a pair of tabs by means of which said mouth may be enlarged.

11. A mumer structure as claimed in claim 9 in which the outer shell is provided with a constricted mouth having a tab` and a tape connection between said tab. and a point on the interior surface of the dust bag for supporting the muilier structure in a position of alinement with the clust connection between one o! said' tabs and afpoint on the interior surface of the-dust bag for supporting the munier structure in alposition of alinement with the dust discharge pipe ot the bag.

collar, a munie? comprising an acoustic absorption material, an outer shell containing said mufiier and .a flexible connection between said muffier and dustbag collar, said flexible connection and outer shell being integral. t

ALFRED E. Noi-mrs.

13. In a vacuum cleaner, a dust bag having a 

